I have NO idea how that one got into my tire - only the head peeked out...
Quick warning: one of the tricks they have here is when you go to fill up your tire with air, a guy nearby will be really helpful and say "I'll help you". He has a nail hidden in his hand and plunges it in your tire when you're turned away. Then when he's "helping" you he says: "hey, did you know you have a nail in this tire?" I can fix it for you (or my friend across the street) only $200 pesos.